Composite rebar for use with quick connect coupling

ABSTRACT

A composite rebar includes a cylindrical body having a cylindrical opening formed therethrough from a first end to an opposing second of the cylindrical body. The composite rebar is formed from a fiber reinforced polymer. The opening is cylindrical in shape and is arranged concentric with an outer circumferential surface of the cylindrical body.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No. 63/065,725, filed on Aug. 14, 2020. The entire disclosure of the above application is hereby incorporated herein by reference.

FIELD

The present invention relates generally to a novel rebar assembly, and more particularly, a rebar assembly including a rebar and a quick connect coupling, wherein the rebar is formed from a composite material and includes an axially extending opening configured to receive a portion of the quick connect coupling therein.

BACKGROUND OF THE INVENTION

The term “rebar” generally refers to a bar or rod used to reinforce another structure such as a concrete structure. Because concrete typically includes a greater strength under compression than tension, the rebars may be typically added to the concrete structure for increasing the tensile strength thereof when subjected to certain loads, such as bending moments tending to cause certain parts of the concrete structure to encounter tensile stresses. It is also common for the outer cylindrical surface of such rebars to be provided with ribs, lugs, indentations, or the like in order to better bond to the concrete and prevent slippage between the concrete and the rebars.

A plurality of the rebars may be arranged into a specific configuration accounting for the shape and expected stresses encountered by the corresponding concrete structure. The resulting rebar assembly may include elongate portions and various corners or turns to account for the corresponding shape of the concrete structure.

Rebar has traditionally been formed from steel based materials with each of the rebars provided as an elongate cylindrical member. Such rebars are generally formed to have standardized lengths and diameters that are then selected to account for the design considerations of the corresponding concrete structure. For example, steel based rebar is typically provided in a variety of different standardized diameters with each of the standardized diameters separated from one another by increments of ⅛ inch, wherein each different diameter is numbered to generally correspond to the number of eighths of an inch utilized (i.e. 3 corresponds to ⅜ inch, 4 corresponds to ½ inch, 5 corresponds to ⅝ inch, etc.). Additionally, such rebars may also be provided in standardized increments of length, such as 10 foot increments. The longstanding use of such standardized sizes of rebars has led to the design of such concrete structures accounting for the use of one or more of these standardized sizes.

A variety of different configurations of the rebars may be necessary to account for various sizes and shapes of the corresponding concrete structure. For example, it may be common for the concrete structure to have a length requiring multiple of the rebars to be aligned in parallel and linked to each other to carry the load of the concrete structure in a desired manner. In order for the load to be properly distributed between a pair of the rebars, it may be necessary for an overlap to be present between the pair of the rebars with respect to the length directions thereof. For example, FIG. 1 shows a configuration wherein a first rebar 3 is arranged parallel to and overlapped with a second rebar 4. The overlap length L present therebetween may typically be selected to be about 40 times the diameter of each of the rebars utilized in the pairing. This need for a coextensive overlap therefore wastes material and increases the weight used and the cost necessary to provide the desired reinforcement under such circumstances.

Additionally, as shown in FIG. 2, there may be instances wherein it may be desirable to bend or curve one or more of the rebars to account for changes in the geometry of the corresponding concrete structure. In FIG. 2, a rebar 5 is bent about 90 degrees at a bent portion 6 thereof to create two perpendicular arranged portions in the rebar 5. Such bending of the rebar 5 may increase the time for installation and necessitate access to certain tools or machinery for forming such bends in the otherwise rigid and elongate rod forming the rebar 5. Additionally, such bends introduce further tension along the exterior corner of the bent portion 6, which may weaken the rebar 5 at the bent portion 6 due to the resulting increase in strain.

In addition to being limited to standardized sizes, steel based rebar also generally suffers from being corrosive, relatively heavy, and conductive both thermally and electrically. With regards to the corrosiveness thereof, it may be common for steel based rebar to be epoxy resin coated to protect the outer surfaces thereof from such corrosion. The use of such coatings adds cost and complexity to the manufacturing process. The other listed shortcomings also must be accounted for when designing the concrete structures utilizing such steel based rebar.

It has become increasingly common to utilize alternative materials such as composites in order to account for the disadvantages of the previously described steel based rebar assemblies. One suitable composite may be a fiber reinforced polymer (FRP). The FRP rebar is non-corrosive, relatively light in weight, and non-conductive in comparison to the steel based counterparts. Additionally, such FRP rebar can be formed to have a greater tensile strength for a given cross-sectional area in comparison to steel based rebar. However, one potential disadvantage of such composite based rebar may be the difficulty in field modifying (bending or otherwise deforming) such composite materials in order to account for certain design considerations of the corresponding concrete structures.

There is accordingly a need for a composite based rebar that is quickly and easily installed while also being capable of being arranged or modified into any variety of different configurations. There is also a need for a composite based rebar that reduces the amount of material necessary due to the elimination of overlaps and other splicing configurations, and especially in comparison to similar configurations utilizing steel based rebar.

SUMMARY OF THE INVENTION

Consistent and consonant with the present invention, an improved composite rebar assembly has surprisingly been discovered.

According to an embodiment of the present disclosure, a rebar is disclosed. The rebar includes a cylindrical body having a longitudinally extending opening formed therein. The opening is configured to receive a portion of a coupling therein.

According to another embodiment of the present disclosure, a rebar assembly is disclosed. The rebar assembly includes at least two rebars. Each of the rebars includes a cylindrical body having a longitudinally extending opening formed therein. A coupling includes at least two coupling shafts. Each of the coupling shafts are received into the opening of one of the rebars.

According to yet another embodiment of the present disclosure, a method of assembling a rebar assembly comprises the step of providing a first rebar wherein the first rebar has a hole formed therethrough. The method further includes the step of attaching the first rebar to a coupling. The coupling has a first coupling shaft configured to be received in the hole of the rebar.

BRIEF DESCRIPTION OF THE DRAWINGS

The above-mentioned, and other features and objects of the inventions, and the manner of attaining them will become more apparent and the invention itself will be better understood by reference to the following description of an embodiment of the invention taken in conjunction with the accompanying drawings, wherein:

FIG. 1 is a schematic left side elevational view of a rebar assembly according to the prior art having an overlap present with respect to a pair of parallel arranged rebar structures;

FIG. 2 is a left side perspective view of a rebar structure according to the prior art having a bent portion for forming a 90 degree angle within the rebar structure;

FIG. 3 is a top perspective view of a composite rebar according to an embodiment of the present invention;

FIG. 4 is a left side elevational view of the composite rebar of FIG. 3;

FIG. 5 is a top plan view of the composite rebar of FIG. 3;

FIG. 6 is a front elevational view of the composite rebar of FIG. 3;

FIG. 7 is a left side elevational exploded view of a quick connect coupling for use with the rebar of FIGS. 3-6 according to an embodiment of the present invention, wherein the quick connect coupling is configured to couple an axially aligned pair of the rebars, and wherein inner features of the rebars are partially shown with phantom lines;

FIG. 8 is a left side elevational exploded view of another quick connect coupling for use with the rebar of FIGS. 3-6 according to another embodiment of the present invention, wherein the quick connect coupling is configured to couple a perpendicular arranged pair of the rebars, and wherein inner features of the rebars are partially shown with phantom lines;

FIG. 9 is a left side elevational exploded view of a rebar assembly including another quick connect coupling for use with the rebar of FIGS. 3-6 according to another embodiment of the present invention, wherein the quick connect coupling is shown as coupling an axially aligned pair of the rebars, and wherein inner features of the rebars are partially shown with phantom lines;

FIG. 10 is a chart equating standardized sizes of steel rebar A-111 with standardized sizes of Glass Fiber Reinforced Polymer (GFRP) rebar; and

FIG. 11 is a chart listing standardized dimensions of GFRP rebar.

DETAILED DESCRIPTION OF AN EMBODIMENT

The following detailed description and appended drawings describe and illustrate various exemplary embodiments of the invention. The description and drawings serve to enable one skilled in the art to make, and use the invention, and are not intended to limit the scope of the invention in any manner. With respect to the methods disclosed, the steps presented are exemplary in nature, and thus, the order of the steps is not necessary or critical.

As used herein, substantially is defined as “to a considerable degree” or “proximate” or as otherwise understood by one ordinarily skilled in the art. Except where otherwise expressly indicated, all numerical quantities in this description are to be understood as modified by the word “about” and all geometric and spatial descriptors are to be understood as modified by the word “substantially” in describing the broadest scope of the technology. “About” when applied to numerical values indicates that the calculation or the measurement allows some slight imprecision in the value (with some approach to exactness in the value; approximately or reasonably close to the value; nearly). If, for some reason, the imprecision provided by “about” and/or “substantially” is not otherwise understood in the art with this ordinary meaning, then “about” and/or “substantially” as used herein indicates at least variations that may arise from ordinary methods of measuring or using such parameters. Where any conflict or ambiguity may exist between a document incorporated by reference and this detailed description, the present detailed description controls. Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section discussed below could be termed a second element, component, region, layer. As used herein “configured to” is a structural term and refers to the structure of the apparatus being disclosed.

FIGS. 3-6 illustrate a novel composite rebar 10 according to an embodiment of the present invention, which is referred to hereinafter as the rebar 10 for brevity. The rebar 10 is formed from a composite material including a resin and a filler material or fiber. The rebar 10 may be formed from a Glass Fiber Reinforced Polymer (GFRP) rebar. The GFRP may be formed from fiberglass in conjunction with a plastic resin. However, other composites having other combinations of fibers and resins may be utilized without necessarily departing from the scope of the present invention. The rebar 10 may be formed in a suitable molding process, as desired, although other manufacturing processes may be utilized. If molding is used, the rebar 10 may be initially provided as a fiber preform received within a corresponding mold into which a molten resin (thermoplastic) material is introduced and then cured to form the desired shape and configuration of the rebar 10 with the fibers positioned and oriented in a desired manner.

The rebar 10 is cylindrical in shape and extends longitudinally from a first end 11 to an opposing second end 12 thereof. The rebar 10 further includes a cylindrical opening 13 formed therein with the opening 13 arranged co-axially and concentrically relative to an outer surface of the cylindrical rebar 10. The rebar 10 accordingly has the form of an elongate hollow cylinder with a greater length than outer diameter. In a provided example, the rebar 10 includes a nominal outer diameter Ø_(OD) of 0.5 inches while the opening 13 has a diameter Ø_(ID) of 0.19 inches (10-32 tapped hole). However, as explained in greater detail hereinafter, the rebar 10 is preferably provided in any number of a variety of standardized outer diameters and opening diameters in addition to that shown and described. The rebar 10 may also include any desired axial length, including being provided in various inch or foot based increments. The composite forming the rebar 10 may be selected to be field modified via a suitable cutting or sawing tool to allow for the rebar 10 to be easily adjustable to any desired axial length for the given application, as desired.

The rebar 10 includes an interference pattern 14 formed on an outer circumferential surface thereof. The interference pattern 14 may be provided as any configuration of ribs, lugs, projections, indentations, or the like extending into or projecting outwardly from the nominal outer circumferential surface for interacting with any surrounding substance encasing the rebar 10, such as but not limited to concrete poured around the rebar 10 when the rebar 10 is used to reinforce a concrete structure. The interference pattern 14 accordingly prevents relative motion between the rebar 10 and the encasing substance via the interfering engagement between the various surfaces forming the interference pattern 14 and the surfaces of the encasing substance adjacent the interference pattern 14. In a provided example, the interference pattern 14 is provided as a pair of diametrically opposed and longitudinally repeating patterns 15 of X-shaped projections extending from the nominal outer circumferential surface. The interference pattern 14 further includes a pair of diametrically opposed and longitudinally extending ribs 16 positioned between the opposing patterns 15 of the X-shaped projections with respect to a circumferential direction of the rebar 10. However, one skilled in the art should appreciate that the interference pattern 14 may take on any configuration suitable for interacting with the surrounding structure while remaining within the scope of the present invention.

As shown in FIG. 6, an inner circumferential surface of the rebar 10 defining the opening 13 may also include a surface feature 18 formed therein. The surface feature 18 may be formed by any pattern of ribs, lugs, projections, indentations, or the like extending into or projecting outwardly from the nominal inner circumferential surface of the rebar 10 forming the opening 13. The surface feature 18 may be provided to be repeated with respect to the longitudinal direction of the rebar 10.

The rebar 10 may be formed to include a dual strain design. The dual strain design may include the reinforcing fibers disposed along each of the outer circumferential surface of the rebar 10 as well as the inner circumferential surface defining the opening 13, as one non-limiting example. The inner circumferential surface may be wrapped with the fibers.

Referring now to FIGS. 7-9 various different quick connect couplings 30, 40, 60 configured for use with a plurality of the rebars 10 are disclosed. Each of the couplings 30, 40, 60 is provided to form a connection between two adjacent ones of the rebars 10 for forming a larger rebar assembly, respectively referred to as reference numerals 300, 400, 600, suitable for implementation into a concrete structure or similarly encased structure.

The coupling 30 of FIG. 7, which may be referred to as a butt connector, is utilized for coupling two of the rebars 10 having ends 11, 12 that are axially aligned and arranged in parallel. The coupling 30 may accordingly be utilized for coupling two elongate rebars 10 for forming a single one of the rebar assembly 300 spanning a greater longitudinal length, thereby allowing for any plurality of the rebars 10 to be coupled together to span a desired length of the corresponding concrete structure. The coupling 30 may be formed from a different material than the corresponding rebars 10 coupled thereto, such as a metallic material. The metallic material may be an aluminum alloy, such as aluminum 6061. However, other metallic materials having similar characteristics of strength, elasticity, and the like may also be utilized.

The coupling 30 includes a primary body 32 and a pair of coupling shafts 35. The primary body 32 extends axially from a first end 33 to an opposing second end 34. One of the coupling shafts 35 extends axially from each of the ends 33, 34 of the primary body 32. The coupling shafts 35 and the primary body 32 are arranged coaxially and concentrically. However, it is understood an offset and non-concentric arrangement can be configured if desired.

Each of the coupling shafts 35 is generally cylindrical in shape and extends axially from a base 36 intersecting the corresponding one of the ends 33, 34 of the primary body 32 to a distal end 37 spaced axially from the base 36. Each of the coupling shafts 35 may extend any suitable axial distance for establishing a desired connection between each of the coupling shafts 35 and a corresponding one of the rebars 10.

Each of the coupling shafts 35 includes a plurality of tapered segments 38 repeated with respect to the axial direction of the coupling 30. Each of the tapered segments 38 tapers radially inwardly when progressing in a direction away from the corresponding base 36 and towards the corresponding distal end 37. Each of the tapered segments 39 tapers radially at a constant rate. In the provided embodiment, each of the tapered segments 38 has the configuration of a truncated cone, thereby resulting in each of the coupling shafts 35 resembling a stacked assembly of the truncated cones. Each of the coupling shafts 35 is configured to be received into a corresponding opening 13 of one of the rebars 10, such as by press-fitting. The tapered segments 38 are configured to provide a one-way interference fit between each of the coupling shafts 35 and the opening 13 into which the coupling shaft 35 is press-fit. Specifically, a tapered conical surface 39 of each of the tapered segments 38 is configured to slide relative to the inner circumferential surface of the rebar 10 defining the opening 13 during axial entry of the coupling shaft 35 into the opening 13 while the surface 39, which is radially inwardly extending, of each of the tapered segments 38 prevents axial removal of the coupling shaft 35 from the opening 13 in a reverse direction away from the restive ends 33, 34 od he primary body 32. The surface feature 18 formed on the inner circumferential surface defining the opening 13 may be shaped and dimensioned to facilitate this relationship with respect to each of the axial directions of the coupling 30.

The primary body 32 of the coupling 30 may include an outer diameter Ø_(ODC) substantially corresponding to that of each of the rebars 10 coupled thereto, such as 0.5 inches, to form a substantially continuous and consistent outer diameter between the coupled together rebars 10 and intervening coupling 30. Each of the coupling shafts 35 may include an average diameter Ø_(avg) substantially corresponding to that of the opening 13, such as about 0.19 inches, for example. It should be apparent that each of the tapered segments 38 may generally include a maximum diameter greater than a minimum diameter of the surface feature 18 of the opening 13 to facilitate the ease of entry and difficulty or removal of the coupling shafts 35 from the openings 13 as described above. The primary body 32 may also be provided to include any desired axial length L_(B), such as 1 inch (double the 0.5 inch diameter), for example.

Although not shown, the different portions of the coupling 30 may be provided to be hollow to minimize the material utilized in forming each of the couplings 30, as desired.

FIG. 7 illustrates an exploded view of the rebar assembly 300, the coupling shaft 35 of the coupling 30 adjacent the first end 33 of the primary body 32 is received into the opening 13 of a first one of the rebars 10 adjacent the second end 12 thereof while a coupling shaft 35 adjacent the second end 34 of the primary body 32 is received into the opening 13 of a second one of the rebars 10 adjacent the first end 11 thereof. The second end 12 of the first one of the rebars 10 is abutted against the first end 33 of the primary body 32 while the first end 11 of the second one of the rebars 10 is abutted against the second end 34 of the primary body 62. The one-way interference fit provided between each of the openings 13 and each of the coupling shafts 35 then prevents undesired removal of each of the coupling shafts 35 from the corresponding first and second rebars 10.

The coupling 40 of FIG. 8 is similar to the coupling 30 in many respects, but is instead configured for coupling two perpendicular arranged rebars 10 for forming a 90 degree joint therebetween to form the rebar assembly 400. The coupling 40 includes an elbow portion 42 and a pair of coupling shafts 55 projecting from perpendicular arranged surfaces 45, 46 of the elbow portion 42. The perpendicular arranged surfaces 45, 46 are formed in cylindrically shaped segments 43, 44 of the elbow portion 42 arranged perpendicular to each other.

Each of the coupling shafts 55 extends axially from a base 56 to a distal end 57. In contrast to the coupling shafts 35 of FIG. 7, each of the coupling shafts 55 includes a cylindrical spacer 59 immediately adjacent the elbow portion 42 to space the corresponding tapered segments 58 from the elbow portion 42. The spacing of the tapered segments 58 via the corresponding cylindrical spacer 59 may be necessary to account for the interaction between the ends 11, 12 of the rebars 10 at a distance spaced from the elbow portion 42 due to the perpendicular arrangement therebetween. The tapered segments 58 are also shown as having a slightly different taper from the truncated conical tapered segments 38 of FIG. 7, but still operate in the same fashion. Specifically, the tapered segments 58 include a variably decreasing slope as the tapered segments 58 extend axially away from the base 56 to form concave surfaces in each of the tapered segments 58. It should be apparent that each of the couplings 30, 40 may include either of the configurations of the tapered segments 38, 58 without significantly altering the use thereof.

FIG. 8 illustrates an exploded view of the rebar assembly 400, the coupling shaft 55 (i.e. the vertical one of the shafts 55) of the coupling 40 adjacent the surface 46 of the elbow portion 32 is received into the opening 13 of a first one of the rebars 10 adjacent the second end 12 thereof while the coupling shaft 55 (i.e. the horizontal one of the shafts 55) adjacent the surface 45 of the elbow portion 42 is received into the opening 13 of a second one of the rebars 10 adjacent the first end 11 thereof. Due to the spacers 59 of the coupling shafts 55, one or both the first one of the rebars 10 or the second one of the rebars 10 may abut the respect surfaces 45,46 or be spaced from the respect surfaces 45, 46 to militate against interference of the rebars 10. The one-way interference fit provided between each of the openings 13 and each of the coupling shafts 55 then prevents undesired removal of each of the coupling shafts 55 from the corresponding first and second rebars 10.

FIG. 9 illustrates a coupling 60 that is substantially identical to the coupling 30 except for a significant elongation of the primary body 62 thereof in comparison to the diameter of the primary body 62. In the illustrated example, the primary body 62 has the axial length L_(B) of 6 inches, for example, when extending from a first end 63 to an opposing second end 64 thereof, as well as a diameter of 0.5 inches, but other dimensions may be utilized. The elongation of the primary body 62 is provided to allow for the primary body 62 to be more easily deformed to accommodate different configurations of the rebars 10. For example, the primary body 62 could be bent about 45 degrees to facilitate the connection of the coupling 60 to a pair of the rebars 10 also arranged at a 45 degree angle relative to each other. The primary body 62 may be bent or otherwise deformed into other configurations, as desired.

FIG. 9 also illustrates the rebar assembly 600 assembled with of a pair of the rebars 10 as would also be consistent with use of either of the couplings 30, 40. A coupling shaft 65 of the coupling 60 adjacent the first end 63 of the primary body 62 is received into the opening 13 of a first one of the rebars 10 adjacent the second end 12 thereof while a coupling shaft 65 adjacent the second end 64 of the primary body 62 is received into the opening 13 of a second one of the rebars 10 adjacent the first end 11 thereof. The second end 12 of the first one of the rebars 10 is abutted against the first end 63 of the primary body 62 while the first end 11 of the second one of the rebars 10 is abutted against the second end 64 of the primary body 62. The one-way interference fit provided between each of the openings 13 and each of the coupling shafts 65 then prevents undesired removal of each of the coupling shafts 65 from the corresponding first and second rebars 10.

Although not illustrated, it should be apparent additional coupling configurations may be utilized in conjunction with two or more of the rebars 10 for forming any number of assemblies. For example, the coupling 30, 40, 60 could include any angle of inclination present between the coupling shafts 35, 55, 65 to accommodate any angle between the adjoining rebars 10. Furthermore, the coupling may be formed with three or more of the coupling shafts 35, 55, 65 extending from a common structure, such as the primary body 32, 62 or the elbow portion 42 to allow for any variety of different configurations of three or more of the rebars 10, such as a cross-shape having four of the coupling shafts 35, 55, 65.

As mentioned throughout, the rebars 10 and the corresponding couplings 30, 40, 60 may be provided to include any number of different dimensions without departing from the scope of the present invention. However, it may be preferable to produce the rebars 10 to have the standardized diameters that are common to already utilized steel or GFRP rebars to allow for an easy substitution of the rebars 10 and couplings 30, 40, 60 of the current invention in place of exiting solutions. For example, FIGS. 10 and 11 include some common standardized sizes of both steel based and GFRP based rebars that may be emulated so that such substitutions can be made without having to significantly redesign exiting models or the like.

The diameter Ø_(ID) of the opening 13 included along the central axis of each of the rebars 10 may also be selected to allow for the each of the rebars 10 to have characteristics similar to or improving upon the standardized sizes utilized for existing steel based or GFRP based rebars devoid of such openings. For example, because GFRP has a greater tensile strength than steel, the diameter OD of the opening 13 relative to the outer circumferential surface of the rebar 10 may be selected so that the rebar 10 has at least the same or greater tensile strength than a steel rebar having the same outer diameter. For example, the illustrated 0.5 inch diameter Ø_(OD) rebar 10 having the 0.19 inch diameter Ø_(ID) opening 13 still has a greater tensile strength than a corresponding 0.5 inch steel rebar devoid of any type of opening or hollowing out. Alternatively, the inner diameter Ø_(ID) of the opening 13 may be selected so that each incremental outer diameter option for the rebar 10 of the present invention is at least as strong or stronger than an adjacent option for an GFRP rebar devoid of such an opening. For example, with reference to FIG. 11, a #3 (inch) GFRP rebar devoid of an opening has a cross-sectional area of 0.110 inches squared, whereas the example rebar 10 has the outer diameter Ø_(OD) corresponding to a #4 GFRP rebar while still having a cross-sectional area of 0.168 square inches. The illustrated rebar 10 having the #4 sized diameter accordingly includes a greater tensile strength (as based on the cross-sectional area) than a corresponding GFRP rebar one standardized size (#3) smaller than the rebar 10 according to the example. In fact, the opening 13 could have a diameter Ø_(ID) as great as 0.33 inches while maintaining the same cross-sectional area and hence strength for the #4 versus #3 comparison. As such, the rebar 10 of the present invention at any of the standardized sizes may be substituted for another standardized size of the GFRP rebar while maintaining at least the same strength thereof.

The rebar assembly 300, 400, 600 utilizing the rebars 10 and couplings 30, 40, 60 of the present invention accordingly provides numerous advantages over the rebar assemblies of the prior art. The inclusion of the opening 13 reduces material usage while maintaining strength. The inclusion of the opening 13 also allows for the couplings 30, 40, 60 to be utilized for forming any number of configurations of the rebars 10, which eliminates the need for overlaps to be present between the rebars 10 as is typical of traditional rebar assemblies. This lack of overlap further reduces the material usage of the rebar assembly 300, 400, 600. The variety of different possible couplings 30, 40, 60 also facilitates an ease of assembly and versatility of the possible rebar assemblies without requiring field modification to the rebars 10 (such as bending). Additionally, in comparison to steel, the use of the composite rebar 10 provides increased strength, the ability for the selection of different fibers for a given application, and the ability to use recycled materials in forming the rebar assembly 300, 400, 600.

From the foregoing description, one ordinarily skilled in the art can easily ascertain the essential characteristics of this invention and, without departing from the spirit and scope thereof, can make various changes and modifications to the invention to adapt it to various usages and conditions. 

What is claimed is:
 1. A rebar comprising: a cylindrical body having a longitudinally extending opening formed therein, the opening configured to receive a portion of a coupling therein.
 2. The rebar of claim 1, wherein the cylindrical body is formed from a composite.
 3. The rebar of claim 2, wherein the composite is a fiber reinforced polymer.
 4. The rebar of claim 1, wherein the opening is cylindrical in shape and is arranged concentric with an outer circumferential surface of the cylindrical body.
 5. The rebar of claim 1, wherein the opening includes a surface feature for engaging the portion of the coupling.
 6. The rebar of claim 5, wherein the surface feature has a pattern repeating along a length of the rebar.
 7. A rebar assembly comprising: at least two rebars, each of the rebars including a cylindrical body having a longitudinally extending opening formed therein; and a coupling including at least two coupling shafts, each of the coupling shafts received into the opening of one of the rebars.
 8. The assembly of claim 7, wherein an inner circumferential surface of the cylindrical body defining the opening includes a surface feature interacting with the corresponding coupling shaft.
 9. The assembly of claim 7, wherein each of the coupling shafts includes a plurality of tapered segments.
 10. The assembly of claim 9, wherein each of the tapered segments tapers radially inwardly when progressing in a direction towards a distal end of a respective one of the coupling shafts.
 11. The assembly of claim 10, wherein each of the tapered segments has a constant decreasing slope.
 12. The assembly of claim 10, wherein each of the tapered segments has a variably decreasing slope.
 13. The assembly of claim 7, wherein the coupling is configured to couple a pair of axially aligned rebars.
 14. The assembly of claim 13, wherein the coupling includes a main cylindrical body, wherein each of the coupling shafts extend axially from a respective end of the main body, and wherein the main body has an outer diameter substantially equal to a diameter of each of the rebars.
 15. The assembly of claim 7, wherein the coupling is configured to couple a pair of perpendicularly arranged rebars.
 16. The assembly of claim 15, wherein the coupling includes an elbow portion, the elbow divided into a pair of cylindrically shaped portions, wherein each the coupling shafts extend axially from a respective one of the cylindrically shaped portions such that the coupling shafts extend perpendicularly with respect to each other.
 17. The assembly of claim 7, wherein each of the coupling shafts includes a spacer.
 18. A method of assembling a rebar assembly comprising the steps of: providing a first rebar, the first rebar having a hole formed therethrough; and attaching the first rebar to a coupling, the coupling having a first coupling shaft configured to be received in the hole of the rebar.
 19. The method of claim 18, further including the step of attaching a second rebar to the coupling, wherein the coupling has a second coupling shaft configured to be received in the hole of the rebar.
 20. The method of claim 19, further including the step of arranging the first rebar perpendicular with respect to the second rebar. 